Key Area 7: Selection Flashcards
What is natural selection?
Natural selection is when a organisms that are best suited as adapted to the environment survive and reproduce, passing on their good genes.
What is sexual selection?
Sexual selection is when the most ‘attractive’ makes are selected by females and they reproduce, passing on their ‘attractive’ genes.
Are natural and sexual selection random or non-random?
Non-random because the processes are not left to chance
What do natural and sexual selection do to genes?
They increase advantageous genes and decrease deleterious genes.
Describe stabilising selection.
When the mean is selected for and the range of values is narrowed to the desired phenotype.
Describe directional selection.
When the mean is selected for and the original mean is shifted to one side.
Describe disruptive selection.
When two means are selected for and the range splits into two extremes of a phenotype.
